The prime minister is reported to have feared that the Bernie Ecclestone affair would finish his career.

But whether the claims are to be believed depends on who knew what and when. The saga began in 1997, even before Labour won its election landslide.

This is how events appeared to unfold:

January 1997 F1 chief Mr Ecclestone donates £1m to the Labour Party, although this is not made public at the time.

May 1 Labour wins a landslide victory in the general election, promising to end government sleaze after a series of scandals under the Conservatives.

May 19 Health Secretary Frank Dobson announces the government will ban all sports sponsorship by tobacco companies.

During the summer, Labour fund-raisers begin secret talks with Mr Ecclestone about a possible second donation, but later break off the discussions.

October 16 1997 Mr Blair has a meeting with Mr Ecclestone, but the discussions remain private.

Sir Patrick Neill: Advice sought

November 5 The government announces proposals to exempt Formula One from a tobacco sponsorship ban after threats the sport would leave Britain. Journalists begin to investigate whether Labour has received donations from Formula One chiefs.

November 7 Public standards watchdog Sir Patrick Neill receives a letter from Labour asking for advice on the donation.

November 10 Chancellor Gordon Brown maintains in an interview with the BBC's Today programme that he does not know whether Mr Ecclestone had contributed to the party.

November 11 The party finally admits the F1 boss had donated £1m in January, but promises to return the money on the advice of Sir Patrick.

November 13 Labour admits Mr Ecclestone offered it money after the May General Election, but it declined. Downing Street cannot confirm the dates involved.

Independent MP Martin Bell calls on the government to reform party funding.

November 14 William Hague demands the minutes of the meeting between Mr Blair and Mr Ecclestone be made public.

November 16 Tony Blair takes the unusual step of apologising on television for his government's handling of the decision to exempt Formula One motor racing from a proposed ban on tobacco advertising, due to come into effect in 2003.

There were threats Formula One racing could leave Britain

Mr Blair says mistakes were made in dealing with the issue, but denies any wrong-doing. Tories say the government's story is "riddled with holes" and dub it the "cash-for-access" affair.

The prime minister also gives in to pressure to publish notes of his meeting with Formula One bosses at Downing Street a month earlier.

November 28 The government is condemned by two cross-party parliamentary committees for exempting Formula One from the tobacco advertising ban.

Public Health Minister Tessa Jowell admits the number of jobs lost if the Formula One left Europe may not be as high as previously estimated.

March 2 1998 Bernie Ecclestone cashes the £1m cheque that Labour returned to him. If it had not been cashed by May, Labour says it would have given the money to charity.

April 1998 The Committee on Standards in Public Life, chaired by Lord Neill, begins its first hearings into political party funding. Part of its task is to investigate whether Labour "sold" access to ministers, including the prime minister.

October 1998 The Neill report recommends an end to foreign donations and full public disclosure of donations of £5,000 or more to political parties.

September 19 2000 Mr Blair and Mr Brown are accused in a book by Labour supporter Andrew Rawnsley of lying to cover up details of the £1m donation. Conservatives call for Mr Brown to resign. Both deny this.